The Stovebolt Site Forums The Shop Area Engine Shop 261 oil dipstick

The 261 in my 55 first series has a 7 1/2" oil dipstick tube(from the lip at the block to the top) and a 15" dipstick. The dipstick tube on my 54 car 235 is about 6" with a 15" dipstick. My guess is that they should both be the same length on the tube (about 6") to read the oil level correctly. Are not the pans on both engines the same capacity?

Most likely the pans will be different.

The 261 is taking about 7 quarts to read full and the 235 takes 6 because it has the canister filter, the 261 has no factory filter therefore should only take 5 quarts. At least I thought so.

Dip stick info:

49-57 Passenger
53-55 Corvette
47-55.1 Comm., Util (ex. D-D, COE)

15 3/32" under washer to tip end
13 5/16" under washer to full line
13 13/16" under washer to add line
---------------------------------------
55.2-57 All (ex. D-D)

15 7/16" under washer to tip end
13 1/2" under washer to full line
14 13/64" under washer to add line
----------------------------------------
58-59 dip stick is different from above
------------
Tube - All
8 7/64" OL
On jobs prior to 1955 cut to 6 3/4"
------------
Oil pan info:
3 different oil pans are grouped below.

53 Pass w/ P.G.
54 All
55.1 Comm., Util.
Same oil pan
--------------------
55.2-57 All same oil pan
--------------------
58-59 All same oil pan

The Master Parts Manual indicates that your dipsticks and tubes may be correct. Note that the note by the dagger says that the tube should be shortened for pre-1955 jobs. The note does not seem to differentiate between 1st and 2 series trucks. Does your 261 have the fixed or floating oil pickup? The type of oil pump and pickup may determine what the oil level in the pan should be. When I installed a GMC oil pump with a floating pickup in my 1954 261 I made a lot of measurements to ensure that I had the correct length tube for my dipstick.

Hoyt

Hoyt

Woah, 261's didn't have a stock filter and 235's did? Somebody better verify this or my whole world is flipped upside down.

I think that's backwards, bud.

Tom, does your info say the 58-59's all had the same oil pan, or the 235's and 261's between 58 and 59 had the same oil pans?

If they are different, could someone please learn us?

No 216s or 235s (USA trucks) came with a "stock" oil filter (meaning standard equipment). The by-pass canister oil-filter was a factory option or accessory.

I am not certain about 1954-57 261 engines (USA trucks) but I think they also did not have a "stock" oil filter, but I might be wrong. 1958-1963 261s have the full-flow blocks, and Shop Manuals for those years always show the full-flow, intake-manifold-mounted canister oil-filter. However, it is possible to run those engines without an oil filter (after making an "adjustment" to the block).

I'm thinking the "Note", in the 57 Master Parts Catalog for the tube,
does not refer to 1st and 2nd series 1955 trucks
because the note is "On jobs prior to 1955". Just a guess.

The oil pan in the Master Parts Catalog,
revised February 1, 1960, is listed as:

58-59 ALL (6 cyl.)

That is a great summary of the dipstick measurements. I just went out and measured the dipsticks on a couple of '58 and later 261s:

15-1/2" under washer to lower tip
13-3/4" under washer to full line
14-23/64" under washer to add line
The tubes extend about 7-1/8" above the block

I also measured a dipstick from a 1953 passenger 235 (the felt) washer was missing):

15-1/32" under washer to lower tip
13-1/4" under washer to full line
13-3/4" under washer to add line
The missing felt washer is probably the difference between my measurements and oilrag's.
The tube extends about 6" above the block (a 1954 261)

it that what we really need to know is how far below the lower flange of the block should the oil level be, with the filter full of oil. It seems that that distance may be not be the same for early and later engines.

Hoyt

I have not been able to find, in my 54 Chevrolet Truck Shop Manual, where it actually says how much oil the engine takes. All my Motors Manuals state 5 qts for all 216 and 235, 6 qts if you have the canister filter, these are the passenger car manuals. Is it safe to say that all 235 and 261's take 5 qts, 6 with filter, irregardless of the dipstick tube and dipstick configuration? Or could my 261 have a higher capacity oil pan?

It is fairly safe to say that all 1954 235/261 truck engines used 5 qts of oil as long as they have the original/stock oil pan and no oil filter.

http://chevy.oldcarmanualproject.com/chevyowner/54tom90.htm

Yes, if you have a 1-qt oil filter, you'd need 6 qts. A 2-qt oil filter was also available on all sizes of 1954 trucks/engines.

Yes, if you have a later oil pan, you could have a different capacity.

I have a spare 54 261, for lack of a better way of knowing if my 55 261's pan had been changed to a later one I guess I could measure and compare them dimension wise. If they are the same then my dipstick and tube configuration must be wrong, hence the tube must be too long since its taking almost 7 qts to read full.

How large is your oil filter? I am running a NAPA 1515 filter and pretty long oil lines. My 261 takes about 7 quarts to read full.

My 55 1st series 261 doesnt have the filter option.

I doubt if a filter was standard/stock equipment on a 261 until maybe 1958.

Just for the sake of a time line, I have 2 59 Bel Air's, 235's, both did not have the oil filter option. I wonder when they were standard for both cars and trucks?.

From what others have said, my own observations since I started driving Chevy sixes in 1953, and the information in the Resto-pack specifications , I do not believe that filters were ever standard on the passenger cars or trucks with 216s or 235s. Bypass filters were available as an RPO on the passenger cars and trucks with 235s. It looks as if the full flow filter was standard on 1958 and later trucks with 261s. You could look in the the other links on this site for more data.

As I look at your dipstick and tube measurements I'm beginning to think that someone has installed the longer tube in your 261 block. This could explain the need for seven quarts of oil. The manual is not clear about the need for a shorter tube for the 55.1 truck engines; however, I thought that they were similar to the 54. I will look at my early and late 261s again tonight (or tomorrow).

Hoyt

There is a comment at the bottom Oil Filters Tech Tip that states that a spin-on filter was used in 1963 230 engines. Most likely it was a standard part of the engine.

Someone else might have info on when an oil filter was a standard part of a V-8 engine.

Now I do have a 59 pass. car 283 that does have the canister type filter down next to the oil pan as part of the block.

Well it is half buried in one of my storage buildings but I was able to check my spare 261 (54). It has about a 6" tube, from block to open end, and about 15" dipstick, from tip to "washer". And this engine has the filter option. Its seaming more and more to me that the tube in my 55.1 is not the stock tube, I looked more closely at it comparing it to the tube in my 54 261 and even noticed that it doesnt have the rolled lip to it where it seats to the block.

All the info posted is from the Master Parts Catalog.
It is possible that the catalog contains errors.
You just never know.

The tube measurement is listed as OL.
Does that include what is seated in the block.

The dip stick listed for,

58-59
ALL (6 cyl.) exc. Ser. (3C-3D-3F)
13 13/16" under washer to full line
14 13/32" under washer to add line

This afternoon I looked at my early and late 261 blocks and noticed that the boss into which the dipstick tube is inserted extends about 2" above the pan flange on the 1954 blocks but only about 1" above the pan flange for the 1958-62 blocks. If the 55.2-57 blocks are similar to the 58-62 bolcks, this explains the need for shorter tubes on the 1954 and 55.1 engines. There still seems to be a 1/4" or so of discrepancy, but some more careful measurements might resolve it. However, a 1/4" is about a half-quart or less of oil. One needs the correct combination of dipstick and tube for each engine. How far below the lowest point of the crankshaft and connecting rods should be the oil level in the pan?

Hoyt

Sorry for the ignorant question: What does"under washer" mean? My 59 has a 261. I was going to change the oil prior to trying to fire it for the first time, and then again after. The first fire. Unfortuntaly, the dipstick at some point lost the cap, and someone just ran some bailing wire through a hole to keep it from sliding down into the motor. I did a google search for oil capacity, and am seeing different numbers, although I am feeling pretty safe putting in 5 quarts just to start it. Thanks, on a side note, where is a good place to buy the right dipstick?

What was the difference in the pans? Was it the profiles or was it the baffles used in the pans. I have 3 spare pans and the have different baffles in them and i cant remember what block each pan came from. Also what was the reason for the oil pickups to change from fixed to the floating or pivot type?

Does it matter what oil pickup you use in year of block or does the pickup only need to match the pan? I ask for a few reasons. #1 I obtained a 261 block that came with nothing and i have to find the right pickup and pan from my stock pile for it. Second i have a 55 235 in my truck now and it has a fixed pickup but the 55 second series manual shows a pivoting one for 55.

as a follow up, the length of my dipstick is 13 13/16" to the top of the shaft from the full line (it has no handle, just a wire run through it). The motor is a 59 261

There is an engine on a well drilling rig that has a casting number 3877178 C followed by a "GM" and a 26. From the research I did, that is a 1962-78 230-250 that was in a few different brands. I think it came out of a truck, but I do not know the year. Anyway, the tube out of the motor is 7", and the one on my truck is pretty near 7". The dipstick in the well rig is slightly shorter, but I think I can use it, just put new marks on it.

My question is, what does "under washer" mean precisely? I need to know where to measure for the new full mark.

Thanks

If the master parts catalog lists all 6 cyl 58-59 (I'm actually surprised it isn't a wider ranger of years), just post something in the parts wanted section. There ought to be a few zillion dipsticks out there from 235s. I probably have one but it's a later block.

I am reviving this thread to add my own findings and to advise what can happen when you have the wrong dipstick!!

I have a 261 with a build date of Feb 1959. My dipstick Tube OL (from the block casting to the end) is approx 7 1/16"

My dipstick from under the washer to the "Full" Line is 13 5/16" (the wrong dipstick)

I had just rebuilt my engine and added one quart at a time to a completely dry engine. Right at 5 qt., without ever turning the engine over, the dipstick read just a fraction below "full".

After oil priming the engine, I added another quart to bring it back to the "Full" line. I have a spin-on oil filter with external oil lines (full flow block). The filter was filled prior to spinning it on.

During the initial run up, after the engine got good and warm, it began to emit blue-gray smoke from the exhaust, had oil on the plugs, and was puffing faint smoke from the breather pipe. I was pretty upset about it all...

I then replaced the factory style valve seals with the umbrella type, as I had noticed that the machine shop had not installed the exhaust seals correctly, but the engine still smoked and I began to doubt myself and wondered if I had installed some rings upside down, or whether the block had been honed properly. Well, as a last resort I drained approx. one quart of oil from the motor, and started it up- no more blue-gray smoke!

I don't know what engine my dipstick is from, but apparently it's the wrong one (based upon this thread) and the full line should be about where the "add" line is.

What a difference a quart makes....